English Abstract

In this research, high performance packing namely, structured packing that combines good heat and mass transfer characteristics with low pressure drop, is proposed for dehumidification of air using liquid desiccants and for regeneration of weak liquid desiccants. This study is concerned with the interface transfer of heat and mass when air is brought into contact with the liquid desiccant solution. A theoretical study of heat and mass transfer analysis in an air-desiccant contact system employing three different liquid desiccants, namely lithium chloride, calcium chloride and a mixture of 50% lithium chloride and 50% calcium chloride (called as Cost Effective Liquid Desiccant, CELD) is investigated. The heat and mass transfer coefficients are evaluated for lithium chloride-air, calcium chloride-air and CELD-air contact systems using gauze-type structured packing as the packing material. The derived transfer coefficients are used to analyze the performance of the dehumidifier and the regenerator. The heat and mass transfer analysis are extended to study the effect of various parameters such as liquid inlet temperature, liquid inlet concentration and its flow rate, air inlet temperature and its flow rate, air outlet humidity, etc. on the performance of the dehumidiier and the regenerator. The performance of structured and random packings are compared and discussed. Moreover, effectiveness of the regenerator and the system pressure drop are calculated and discussed.